Caller: Scammer-allegedly National Australia Bank

Scammer called from noisy Indian call centre claiming to be National Australia Bank. Calling to check on funds transfer of $800 to John Smith in America for MEDICAL Donation. When asked when I last authorised a transaction online for this account, I asked to re-confirm it was National Australia Bank. The caller immediately hung up. This is likely due to the previous call less than an hour before where it was Commonwealth Bank Security. Same payee name but only $300. When he answered yes to my request to confirm Commonwealth bank, I responded with 37 Years ago so F** off and stop wasting my time on spam calls (no Commbank account held since childhood). He replied "you F*** off too" and hung up.